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作者：ROSNER, GL; TSIATIS, AA
作者单位：Harvard University; Harvard T.H. Chan School of Public Health
摘要：With interest in designing group sequential clinical trials increasing, methodology for analysing the data arising in such trials is needed. We discuss several approaches to constructing confidence intervals for the parameter of interest in a group sequential trial after the trial has ended. We compare these methods to one already in the literature and point out interesting differences.
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作者：FRASER, DAS; REID, N
作者单位：University of Toronto
摘要：A one-dimensional conditional procedure defines a partition of the sample space into curves which can be represented by means of a unit vector field. A formula is given for the conditional distribution in terms of local properties of the vector field. Conditions are developed for reducing the first-order effects of nuisance parameters and reproducing to higher order the likelihood changes for the parameter of interest. The emphasis is on extending exponential family methods after locally appro...
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作者：MEHTA, CR; PATEL, NR; WEI, LJ
作者单位：Indian Institute of Management (IIM System); Indian Institute of Management Ahmedabad; University of Michigan System; University of Michigan
摘要：In a clinical trial comparing two treatments, suppose that subjects are assigned sequentially to the treatment groups by a restricted randomization rule. Under the randomization model, an efficient recursive algorithm is provided to generate the exact permutational distribution for linear rank statistics, given the final imbalance between the number of patients in the two groups. If only the significance level of the test is required, the efficiency of the algorithm can be improved significant...
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作者：RAFTERY, AE
摘要：A hierarchical Bayes approach to the problem of estimating N in the binomial distribution is presented. This provides a simple and flexible way of specifying prior information, and also allows a convenient representation of vague prior knowledge. It yields solutions to the problems of interval estimation, prediction and decision making, as well as that of point estimation. The Bayes estimator compares favourably with the best, previously proposed, point estimators in the literature.
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作者：SKINNER, CJ
摘要：A ''discontinuity'' of sampling distribution inference between a prediction problem and an estimation problem in model-based survey sampling is discussed. The problem is resolved by conditioning on an appropriate ancillary within a curved exponential family framework. The ignorability of the sampling design for inference is discussed.
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作者：NAYAK, TK
摘要：A design called recapture debugging is proposed to get extra information to estimate the original number of faults, N, in a reliability system. The system is observed for a fixed amount of time .tau. and the failures are assumed to follow an exponential law with an unknown common parameter .lambda.. The maximum likelihood and moment estimators of N and .lambda. are derived and compared with the existing estimators. The recapture sampling provides substantially more information and improved est...
